1. Field of the Invention
This invention relates to a ratchet spanner, and more particularly to a driving shaft for a ratchet spanner, which can be coupled with a selected one of a wrench sleeve and a head of a screwdriver.
2. Description of the Related Art
Referring to FIG. 1, a conventional pneumatic ratchet spanner is shown to include a handle 1 with a driving mechanism (not shown) disposed therein, a ratchet seat 2 disposed at a front end of the handle 1, and a ratchet device 3 disposed within the ratchet seat 2 and driven by the driving mechanism (not shown). The ratchet device 3 includes a polygonal driving shaft 301 and a sleeve-retaining member 302 that is configured as a spring-biased ball, which is biased to project outwardly of the driving shaft 301 so as to press against a wrench sleeve (not shown) sleeved on the driving shaft 301, thereby retaining the wrench sleeve (not shown) on the driving shaft 301. The driving shaft 301 suffers from the following disadvantages:                (1) The driving shaft 301 cannot be connected directly to a head of a screwdriver for rotating the same.        (2) It is difficult to mount the sleeve-retaining member 302 on the driving shaft 301.        